#define _CRT_SECURE_NO_WARNINGS 1
#include<stdio.h>
int ownlen(char* a)
{
	int i = 0;
	int count = 0;
	while (a[i] != '\0')
	{
		count++;
		i++;
	}
	return count;
}
oppositechange(char* a)
{
	int left = 0;
	int right = ownlen(a)-1;
	while (left < right)
	{
		int j = 0;
		j = a[left];
		a[left] = a[right];
		a[right] = j;
		left++;
		right--;
	}
}
int main()
{
	char arr[] = "abcdef";
	oppositechange(arr);
	printf("%s", arr);
	return 0;
}